package main

import (
	"bytes"
	"fmt"
	"strings"
)

func main() {
	str1 := []string{"hello", "world", "!"}
	res := strings.Join(str1, "+")
	fmt.Println(res)  // hello+world+!

	res1 := bytes.Join([][]byte{[]byte("hello"), []byte("world")}, []byte("+"))
	fmt.Printf("%s\n", res1)
}
